Setting idle
Thread Starter
Joined: Jun 2005
Posts: 4,641
Likes: 392
From: cookeville, TN
Setting idle How can you get the iac valve to plug its bipass to set the idle set screw? It's a 99 btw
I tried to search on it but couldn't find an answer
I tried to search on it but couldn't find an answer
Last edited by blackbyrd; Jul 12, 2015 at 01:34 PM.
There is a process. You turn the set screw and then do a tps relearn. Unplug tps , turn key to on (not run)for 30seconds. Turn key off, plug it back in and restart engine. Using a scanner that you can at least read your tps position and actual idle speed is helpful. I used a scanner and had to repeat this a number of times. Turn the idle set screw a little each time. The iac and idle are controlled by pcm. Some say never to touch it. I had a slight high idle that I could not get rid of. I must have moved the set screw when I took my throttle body off once. Because I eliminated all vacuum leaks etc before I finally tried this. I chased the condition for quite a while before I figured it out.
Last edited by celtsean; Jul 12, 2015 at 07:20 PM.
Thread Starter
Joined: Jun 2005
Posts: 4,641
Likes: 392
From: cookeville, TN
Thanks
I adjusted mine prior to a tune, and now its so low the engine wont stay running unless I keep my foot on the throttle. My tach says with my foot on it im just under 1k rpm. We thought the idle was related to a different issue, but we ruled it out and since I messed with it not long ago when I found there was some slack in the throttle cable and after adjusting it the car was idleing too high.
ill see if I can get it adjusted and running after I swap my passenger upstream o2 out
I adjusted mine prior to a tune, and now its so low the engine wont stay running unless I keep my foot on the throttle. My tach says with my foot on it im just under 1k rpm. We thought the idle was related to a different issue, but we ruled it out and since I messed with it not long ago when I found there was some slack in the throttle cable and after adjusting it the car was idleing too high.
ill see if I can get it adjusted and running after I swap my passenger upstream o2 out
Thanks
I adjusted mine prior to a tune, and now its so low the engine wont stay running unless I keep my foot on the throttle. My tach says with my foot on it im just under 1k rpm. We thought the idle was related to a different issue, but we ruled it out and since I messed with it not long ago when I found there was some slack in the throttle cable and after adjusting it the car was idleing too high.
ill see if I can get it adjusted and running after I swap my passenger upstream o2 out
I adjusted mine prior to a tune, and now its so low the engine wont stay running unless I keep my foot on the throttle. My tach says with my foot on it im just under 1k rpm. We thought the idle was related to a different issue, but we ruled it out and since I messed with it not long ago when I found there was some slack in the throttle cable and after adjusting it the car was idleing too high.
ill see if I can get it adjusted and running after I swap my passenger upstream o2 out
Thread Starter
Joined: Jun 2005
Posts: 4,641
Likes: 392
From: cookeville, TN
My scantool doesnt provide IAC counts, even adjusting the screw and relearning the tps i cant get it to idle and if I let my foot out of it she dies and I adjusted it quite a bit and there was no change in idle speed.
im about to pull my multimeter out an dcheck the TPS and see what its actually set on
im about to pull my multimeter out an dcheck the TPS and see what its actually set on
Thread Starter
Joined: Jun 2005
Posts: 4,641
Likes: 392
From: cookeville, TN
Got hp tuners, still having idle issues. I was looking at the iac position pid with vcm scanned and at idle it was at 175 and really didn't move. went to 174 for a bit but that's about it. Is it toast?
I know my plugs are fouled again because its running rich and has some injector pulse issue and o2 bank 1 issue. But I really need to get it to idle without my foot on the gas . before I go any further with that..
I know my plugs are fouled again because its running rich and has some injector pulse issue and o2 bank 1 issue. But I really need to get it to idle without my foot on the gas . before I go any further with that..
Let me back up a little. Is this car stock or is the Firebird in your sig?
If it's the bird you are going to have to go in and set the minimum air flow and a few other things.
Also if it's the bird this really needs to be in the tuning section for best results.
It it's stock IMO it's in the right place.
Let me know what you're working on go from there.
If it's the bird you are going to have to go in and set the minimum air flow and a few other things.
Also if it's the bird this really needs to be in the tuning section for best results.
It it's stock IMO it's in the right place.
Let me know what you're working on go from there.
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Thread Starter
Joined: Jun 2005
Posts: 4,641
Likes: 392
From: cookeville, TN
Yeah it's the bird.....super not stock
Got a chance to.learn a bit more about the iac and HP tuners. At the value I stated 175 is pretty much open, so its not what's causing my idle issue.
My tune is so jacked up ( not by my doing) but I have some other issues going on as well. I'm still learning HP tuners as I just got it on thursday. At this point I think my best bet is to take it back to a stock tune and rework it from scratch. It won't idle, its running wayyyyyy to rich and its fouled a set of 2 month old plugs to boot.
I got my work cutout for me on this one. It's like I'm having to relearn everything I did as I built the car 7 years ago and ended up broke and unable to get a final tune not knowing the state it was in.
Got a chance to.learn a bit more about the iac and HP tuners. At the value I stated 175 is pretty much open, so its not what's causing my idle issue.
My tune is so jacked up ( not by my doing) but I have some other issues going on as well. I'm still learning HP tuners as I just got it on thursday. At this point I think my best bet is to take it back to a stock tune and rework it from scratch. It won't idle, its running wayyyyyy to rich and its fouled a set of 2 month old plugs to boot.
I got my work cutout for me on this one. It's like I'm having to relearn everything I did as I built the car 7 years ago and ended up broke and unable to get a final tune not knowing the state it was in.
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Verdad Gallardo Yeah it's the bird.....super not stock
Got a chance to.learn a bit more about the iac and HP tuners. At the value I stated 175 is pretty much open, so its not what's causing my idle issue.
My tune is so jacked up ( not by my doing) but I have some other issues going on as well. I'm still learning HP tuners as I just got it on thursday. At this point I think my best bet is to take it back to a stock tune and rework it from scratch. It won't idle, its running wayyyyyy to rich and its fouled a set of 2 month old plugs to boot.
I got my work cutout for me on this one. It's like I'm having to relearn everything I did as I built the car 7 years ago and ended up broke and unable to get a final tune not knowing the state it was in.
Got a chance to.learn a bit more about the iac and HP tuners. At the value I stated 175 is pretty much open, so its not what's causing my idle issue.
My tune is so jacked up ( not by my doing) but I have some other issues going on as well. I'm still learning HP tuners as I just got it on thursday. At this point I think my best bet is to take it back to a stock tune and rework it from scratch. It won't idle, its running wayyyyyy to rich and its fouled a set of 2 month old plugs to boot.
I got my work cutout for me on this one. It's like I'm having to relearn everything I did as I built the car 7 years ago and ended up broke and unable to get a final tune not knowing the state it was in.
Thread Starter
Joined: Jun 2005
Posts: 4,641
Likes: 392
From: cookeville, TN
yeah a friend of mine sent me some not so light reading on tuning and has been using HP tuners for a while. Learned a lot form talking with him over the years just never made the leap to doing it on my own. I have been perusing the write ups and stuff on here learning the theory behind it all. Looking forward to playing around with it, just gotta get some other issues resolved i think. Granted for a majority of the tuning you disable what I am having issues with so I could dial in my tune and than just transplant the file onto the new ecm if that ends up being my issue.
Granted the day for me is playing around with DAQ systems for lab equipment, calibration and post data processing is right in my wheel house....just in a different application
Granted the day for me is playing around with DAQ systems for lab equipment, calibration and post data processing is right in my wheel house....just in a different application